Internal-combustion engine



April 1946. r L. E. JOHNSON ET AL 2,398,182

INTERNAL COMBUS TION ENGINE Filed Aug. 25, 1945 4 Sheets-Sheet 1 :E :r: l '7 7 mmvroxs. Lie 0 E. Johnson Y Car 2. Maxwell April 9, 1946. L. E. JOHNSON ETAL INTERNAL-COMBUSTION ENGINE 4 Sheets-Sheet 2 Filed Aug. 25, 1943 IN VEN TORS L l 0 ya E Johnson C'ar/ ,8. Maxwell April 9, 1946.

1.. E. JOHNSON ET AL ,3 82 INTERNAL-COMBUSTION ENGINE Filed Aug. 25, 1943 4 Sheets-Sheet 4 INVENTORS. [Joye/E. Johnson 24 i! BY Carl E. Maxwell ATT RNEY Patented Apr. 9, 1946 Lloyd E. Johnson,

I well County,

Fon du'Lac Township, Tueand Carl R. Maxwell, W

111., assignors to Caterpillar Tractor Co., San

Leandro,

Calif., a corporation of California Application August 25, 1943, Serial No. 499,392

4 Claims.

Our invention relates to internal combustion engines, and more particularly to a radial internal combustion engine having solid fuel injection mechanisms.

Such type of engine presents the matter of providing mechanism for actuating and controlling the fuel injection mechanisms, and also for actuating valve tappet mechanisms associated with the cylinders on the engine. Our invention is primarily directed to such features, and has as its objects, among others, the provision of improved means for actuating and controlling the fuel injection mechanisms. and for actuating the cylinder valves; which is of relatively simple and economical construction; relatively easy to assemble; and which provides for accurate timing relationship of the fuel injection mechanisms. Other objects of our invention will become apparent from a perusal of the following description.

Referring to the drawings:

Fig. 1 is a sectional view alongthe crankshaft axis, of a form of radial internal combustion engine embodying the construction of our invention; parts being omitted from the view to disclose the construction more clearly and other parts being shown more or less schematically.

Fig. 2 is a fragmentary transverse section in a plane indicated by line 2-2 in Fig. 1.

Fig. 3 is a developed vertical sectional view, partly in elevation, injection pump mechanism embodied in the engine.

Fig. 4 is a horizontal sectional elevation taken in planes indicated by line [-4 in Fig. 3.

Fig. 5 is a more or less schematic fragmentary section, illustrating the fuel passage arrangement in the engine.

Fig. 6 is a fragmentary section of a portion of the structure illustrated in Fig. 1; the view being enlarged compared to Fig. 1 to illustrate such structure more clearly. v

Fig. 7 is a horizontal sectional elevation taken in a plane indicated by line 1-1 in Fig. 2.

Fig. 8 is a horizontal sectional elevation taken in planes indicated by line 8-8 in Fig. 2.

Fig. 9 is a fragmentary vertical section taken in a plane indicated by line 99 in Fig. '7.

Fig. 10 is a fragmentary vertical section taken in a plane indicated by line lO-IO in Fig. 7.

With particular reference to Figs. 1 and 6, the engine illustrated is a radial Diesel or compression ignition engine. However, it is to be underemployed in any other type of radial internal combustion engine. such as one of the spark ignition type having solid fuel injection mechanisms thereon. The engine comprises a crankcase 2 having a plurality of peripherally or circumi'erentially disposed cylinders 3; the cylinders being preferably of the air cooled type and having cooling fins l. A precombustion chamber 6 is mounted in the head of each cylinder 4, and supports a fuel injection nozzle I of any suitable construction, which is connected to a fuel line 8 in turn connected, to a fuel injection pump to be subsequently described.

Detachably connected to crankcase 2 by suitable screws or studs (not shown) adapted to pass through apertures 8 (shown in Fig. 2), is a nosepiece member H. Nosepiece II is mounted against one wall l2 of the crankcase, which wall has an annular flange I! in which is located one bearing structure ll for crankshaft l8; such crankshaft It being also journalled in a suitable bearing structure 11 located in the opposite wall 18 of the crankcase. As is customaryin radial internal combustion engines, the crank bearing I9 of crankshaft I licarriesthe large end of the master connecting rod 2| connected in turn to one of pistons 22 in one of cylinders 3; auxof a preferred form of fuel vided with suitable packing stood that the features of our invention may be 'iliary connecting rods 22 being connected to the remaining pistons 22. Crankshaft l6 extends through nosepiece II; and the projecting portion thereof is journalled in another bearing structure 24 positioned in an aperture formed in the outer wall 26 of nosepiece H; the outer race of bearing structure 24 being retained in position by means of a ring member 21 (specially shaped for a purpose to be subsequently explained) adjacent the inside face of nosepiece wall 28, and by a retaining plate 28 adjacent the outside face of nosepiece wall 26. Ring member 21 andretainer plate 28 are detachably secured to wall 26 by means of bolts 29 and nuts 3|.

A portion of crankshaft l6 adjacent bearing structure H is splined at 32; and on such splined portion 32 is secured a driving pinion orgear 33 for driving gearing for a purpose to be subse; quently explained. A ring 34 is positioned between the inner race of bearing structure I and one end of the hub of pinion l3; and another ring 36 i positioned between the opposite end of the hub of pinion-33 and the inner race of bearing structure 24. Rings 34 and 36, which are proor sealed rings 25 in the Periphery thereof, also serve as spacers for the described assembly on. the -:rankshaft; and the entire assembly is held together by means of a nut 31 screwed on the crankshaft, and which is also provided with packing or sealing rings 31' in the periphery thereof to seal the aperture in retainer plate 28.

A flywheel M is secured to the projecting end of crankshaft It, and is provided with a ring gear 42 to enable engagement thereof with start= ing mechanism (not shown). A cooling fan 43 is also secured to the crankshaft; flywheel M and fan 43 being enclosed by a cover structure 44 provided with omnings 49 for direction of cooling air against the cylinders of the engine. Suitable gearing ll is connectedto the crankshaft, through a suitable clutch ll; for driving of mechanism (not shown) adapted to be driven by the engine.

Peripherally mounted on the rim of nosepiece iI adjacent wall I2 or. the crankcase, are a pinrality of substantially radially extending valve tappet mechanisms SI, of any suitable construction, associated with each cylinder 3 of the engine. These tappet mechanisms include the usual cam engaging rollers 52 at their inner ends and tappet rods 53 connected to the inlet valve and the exhaust valve (not shown) of each cylinder. Valve cam means 54 engaging cam rollers 52, is provided for actuating the valve tappet mechanisms; Such valve cam means 54 comprises a ring member having an outer flange 58 provided with rim portions 51 which have the usual cam lobes over which cam rollers 52 are adapted to ride. An inner flange 58 is also formed on valve cam means 54, and is journalled on annular flange I3 on crankcase wall I2; a suitable bearing 59 being positioned between flange I3 and flange 58. An annular plate BI is detachably ecured to flange l3 by means of cap screws 52 to hold valve cam means 54 in position; and integral with such plate is a bearing bracket portion 53, having sleeve portion 64 in which is Journalled a hub 86 having gearing thereon tor driving valve cam means 54 from the engine.

Such gearing includes a spur gear 61 splined on one end portion of hub 68, and meshing with internal gear teeth 68 on the inside of outer valve cam flange 56; the splined connection icetween spur gear 61 and hub 58 enabling such hub to be inserted through sleeve 54 ior connection with gear ill. To retain the hub in position, a bolt 68 is provided, which has en larged head ll adjacent one end thereoi adapted to engage gearand at its opposite end, belt 538 screwed thereon nut it provided with a flange l3 drie t ed to en the opposite end of hub 65. a driven spur '74 is formed integral with hub lit, and meshes with driving gear or pinion. at on crankshaft it. Thus, it is seen that when the engine operating, valve cam means M will be driven through gears 33, M and 61.

Fuel injection pumps ti, one for each cylinder 0! the engine, are peripherally 0r circumferentially disposed about the rim of noscplece II,

adjacent outer wall 28 of such noseplece. Each of the pumps is oi the type having a reciprocable plunger adapted to meter fuel by angular adjustment oi the plunger about its axis, as it is reciprocated. Any suitable pump of this type may be employed in the arrangement of Our invention, but we prefer to employ the type of pump which is described in detail and claimed in our assignees co-pendlng application, by Lloyd E. Johnson, Serial No, 499,891, filed Aug. 25,1943.

Briefly, each pump comprises a. pump casing 82 having a pump cylinder or barrel 83 in which Ill speec es a pump plunger M is mounted for axial reciprocation, and angular adjustment about its axis; the inlet of fuel being provided by a fuel inlet passage 86 formed in pump casing 82 and in communication with fuel inlet port or orifice 81 formed in the wall of barrel to. A fuel return passage 83 in communication with inlet passage M5 djacent orifice ill, is provided in association with a ierrule or tube 89 in inlet passage t5 for 15116 purp se or bleeding air, as is described in the previously mentioned loo-pending application. Adjacent its discharge end, pump plunger M is formed with the well-known annular groove 9! and slanting or scroll edge M, adapted to work past inlet port ill and thu control the quantity of fuel ejected as the plunger is reciprocated and angularly adjusted.

The tappet end of plunger 8! extends into a guide sleeve 93 slidably mounted in casing 32, and which engages pump tappet mechanism M rcmovably positioned in the rim or nosepiece II. Such tappet mechanisms 94 extend substantially radially, and each includes a sleeve 88, having an outer flange 91 supported in a recess in the rim of nosepiece I I and containing a slidahly mounted crosshead member 55 carrying a cam engaging roller 98. A tappet stem or screw IOI is adjustably mounted on crosshead 98 in free engagement with guide sleeve 93. Movement of tappe: mechanism 94 in a substantially radially outward direction, by suitable cam means to be subsequently described, causes reciprocation of pump plunger 84 in one direction for fuel injection; while the return or suction stroke of the plunger is effected by means of a coil spring I02 interposed between a flange in pump casing 52 and a retainer plate I03 adjacent guide sleeve 93.

Gearing is provided in pump casing I! to enable angular adjustment of pump plunger 54, comprising a gear member I04 secured to the tappet end of plunger 84, and having teeth extending through a slot in guide sleeve 9! and which mesh with another gear member I" journalled in pump casing 82 at the side of gear member I. Each of such pump casings 92 with the described pump mechanism therein is detachably connected to nosepiece II by cap screws I01; and such nosepiece contains means for effecting angular adjustment of all the pump plungers simultaneously, as well as means for actuating the pump tappet mechanisms.

The means for actuating the pump tappet mechanisms comprises annular pump cam ii! lobes ill? over which the cam rollers 39 of the pump happet mechanism ride. Cam I I I is journolled for rotation on an inner flange H3 formed on ring 21 which thus serves as a bearing member, and is retained in position on such flange by a detachabiy secured retainer plate I I4. It will be noted that the journal bearing at III for pump cam I l i is substantially radially in line with the pump tappet mechanisms 94; and the pump tappet mechanisms bear directly on the cam. This arrangement avoids deflection, and thus insures true movement oi! pump plungers N with consequent accurate fuel metering.

To enable drivingot pump cam III fromthe driving means associated with valve cammeans 54, pump cam III is provided adjacent the periphery thereof with an annular flange I I5 having internal gear teeth III in mesh with a spur gear III integral with hub Ii. Thus, common means driven from the engine is provided for driving valve cam means 54 and pump cam III, which includes spur gear II! meshing with inv a 2,898,189 ternal gear teeth II1 on the pump cam, makingv for an extremely compact and simple arrange ment. It will be noted that the described gearing is such as to drive the valve cam and the pump cam at a reduced speed compared to engine speed because of the speed reduction provided by gears 33 and 14; pump cam III having the correct number of lobes to impart proper timing to the fuel injection pumps.-

The means for angularly adjusting pump plungers 64 to effect proper metering of fuel is governor controlled, and includes a ring gear I2I journalled on an outer flange I 22 formed on bearing ring 21, and which has face teeth I23 meshing with a plurality of spur gears I24. Each of spur gears is formed at the lower end of a turntable rod I26 detachably connected to the gear member I06 in each pump casing 62. As can be noted more clearly fromFigs. 2, 3 and 4, the outer end of each rod has secured thereto a collar member I21 having a recess I26 therein adapted to receive a pin I26 on an associated pump gear member I 66, thus providing a detachably pin-typ coupling or connection between the gearing in each pump casing 62 and each rod I26. As a result, when all the rods I26 are turned about their axis by rotation or turning of ring gear I2 I, all pump plungers 64 will be turned simultaneously to the same extent and in the same direction, resulting in uniform metering of fuel by all of the injection pumps.

Means is providedfor detachably supporting rods I26 in nosepiece member II for ready assembly therein, and detachable connection of spur gears I24 with ring gear I2I when such rods are assembled. With reference to Figs. 2, 3 and 6, each rod I26 is journalled in a sleeve I3I; bushings I32 being positioned between the end portions of each rod I26 and the associated sleeve. The outer end of each sleeve I3Iis formed with a flange I33 adapted to seat on a shoulder I34 formed adjacent the rim of nosepiece I I; collar member I21 on each rod I26 being detachably secured to such rod over the outer bushing I32. The inner end of each sleeve I3I engages a lug or bracket I36 formed integral with the inside face of wall 26 of nosepiece member II; and each of such brackets I36 is provided with an aperture therein through which the sleeve and associated rod are lnsertable or removable. Thus, each sleeve and its associated rod are supported, and positioned or centered by an associated bracket I36. In this connection, the spur gear I24 on each rod I26 is small enough in diameter to pass through the aperture in the associated'bracket I36.

From the preceding description, it is seen that turning of ring gear I2I effects turning'of rods I26 which, through the described detachable connections with fuel injection pumps 8|, cause angular adjustment of the plungers in such pumps. By virtue of the detachable connections between rods I26 and pumps 3I, the pumps may be readily attached or detached from the engine without disturbing the rods; and prior to attachment of pumps 6|, rods I26 and their associated sleeve assemblies may be readily attached to the engine to mesh spur gears I24 with ring gear I2I. The provision of face teeth I23 on ring gear I2I, adapted to mesh with spur gears I24, results in an important functional advantage because this eliminates the necessity of having to center, gears I24 properly in a. radial direction to adjust them for back lash so that all thefuel injection pumps may meter accurately, which would be necessary of the engine. However,

'rangement of the 'flange I44 detachably connected of spur gears I 24.

Pump tappet mechanisms 64 extend radially control rods I26 and their associated sleeve I 3|, although they may be considered as extending substantially radially of the engine, are offset slightly from true radii. This is desired in order to enable a .compact are plunger control mechanism in pumps. To compensate for such offsetting of rods I26, the face teeth I23 on ring gear I2I are also oi'fset radially by an amount corresponding to the radial offsetting of the rods. Thus, spur gears I24 will mesh accurately with teeth I23 on ring gear I2I.

As was previously mentioned, angular adjustment of the pump plungers is governor controlled. Our preferred mechanism enabling such control is illustrated in Figs. 2, 7, 8, 9 and 10, and includes adjustable means to obtain a proper setting thereof. This mechanism comprises shafting I4I journalled in a sleeve I42 adjacent its inner end by means of suitable bearing means I42; and having at such end a spur gear I43 meshing with face teeth I23 of ring gear I2I. The outer end of sleeve I42 is formed with athe fuel injection nosepiece II; while the is positioned and centered viously described for each sleeve I3 I, in a bracket or lug I46 similar to each bracket I36. Shafting I4I extends .through a sleeve extension I41 detachably connected over the flange of sleeve I42, by means of cap screws I46; and to the projecting end of such shafting I is connected a hub I49 of a lever I6I which in turn is pivotally connected to a suitable governor linkage I52 which is connected to the engine governor (not shown).

For obtaining proper setting of the described mechanism, relatively adjustable plates are provided. One of these plates I63 is fixedly secured to a flange I54 on extension sleeve I41, by cap screws I66; 9, bearing structure I61 being provided in plate I53 to provide another journal for shafting I 4I adjacent its outer end. Mounted for angular adjustment about a flange. I 61' on plate I53 is an adjustable plate I66 which has arcuate slots I69 therein through which extend cap screws I6I in plate I63 for securing adjustable plate I56 to plate I63, after plate I56 has been angularly adjusted to a proper position. Angular adjustment of plate I66 is effected by means of a disk I62 joumalled in plate I63, and which has a pin I63 eccentrically mounted thereon and projecting through a slot I64 in adjustableplate I56. By turning disk I62, adjustable plate I58 can be turned, by virtue of engagement of pin I63 inslot I64.

Projecting outwardly from hub I46 is an arm I66 which is adapted to move against a stop pin I61 secured to fixed plate I 63 and extending through one of the arcuate slots I53 in adjustable plate I68. Stop pin I61 determines the shut oil position for the fuel injection pumps which will be always fixed. The full load stop I68 against which arm I66 is also adapted to move, is fixed to adjustable plate I 66. Consequently. adjustable plate I66 provides for proper spacing between the stops I61 and I66. Plate I56 may be adjusted in the manner previously described, to

enable proper positioning of the full load stop. In case a permanent setting is desired after initial adjustment, a lock pin I66 may be pressed to the rim inner end of sleeve 1 in the manner pre- 4 through suitable minim, in fixed mm in mm adjustable plate $8, an is. indicated in mg ii.

Passages are provicimi engine, communicating with passages 83% nmi iii in fuel injection pump casing M 01- cimuiciiic". of fuefi. An annular mimimici passage pmvizieiii in imscpiece M, anti in wen to the can Iacc iiicrcmf 5m mmfi iyinn me] in thc P thmugi wiiniiycziiciiiiing incimgcs ii?! W to cum miccie wi i minim wmages W; 58m v ems, Mai pmvicicai m; the oi? gp es and J m mammal msmiiclid. passages WE nice mi'mcii i i is npen in Mimi incc M iiic Such pcamcre GM ccmmimicnicn with in i tending Hi i immmmiicc the pump iuiei iJ%T/il'i"i1 1i WE; $91111" Min pimrides c. semi an" iii and, 13M 0 im dc 0i. .csepicce ii. innniiclci 11s: Jifl s iii a", i; isicr i mine iii? in a. mini,

haw L film ,i 4 A by a fuel H1118 m mciiii'ciii the return. nwniiniii imwgn SM is cm. a. fuel line Kim tn the We cicim:

1. In n radial interim cumimM-icn en ing a pluraiity 0i ciaa'cumierenticiiiy (lisp injection pumps, each'ufl ii'i'iicii has a reciprccct able plunger 0i the tyne Whwein. metei mg cf :fuei is controlled by angular adjustment 0f the piunger; mechanism Icr nnguisiriy adjusting the mung ers comprising a ring gear jmu'nalied in the em gine and having lace teeth, c plurality of IDiiS each of which has at its outer end mews con nected to a plunger to turn it and a spur gem at its inner end,m mesh with the face teeth, said means for turning the ring gear including a. rod having a. spur gear in mesh with the face teeth.

in than ncsepiccc ci inc ammac 2. In a mm internal combustion engine haw ing a. incl injeciion pump including a reciprocatnbic plunger ct the type wherein metering of mm is mmtmiled by angular adjustment of the niimgeir, mechanism 101' nngulnriy adjusting the piling @cmgmcining rcd having at its cuter end means ccmnccied m the plunger in tum it and am new" m its inner and, a sleeve in which the rod is jC-MWUHE'IZL and. c. bracket in the engine In:

" @3119 sic-cw and iinviing an, aperture a icy cnguimiy adjusting a. :fi'ucl iii-2w piimger 01 the type wiicmin meccniwciied by nnguim :mijuistngcr ccmprising n, mrl having acicim ihmimii which the finscimbic c mnw'mbic.

riispcccfl L sici injcnticn pumps cietncimialy mount On the mccpicce member; each 01% "the pimps having a, recipi'ccataiiie plunger 0! the Wpe wherein metering 0i Zuel in contmileci by angular acijustmeni; oi the plunger; a bearing ring detachabiy mounted an the nnsepiece; mechanism for anguiarly adjust-mg the plungers cnmprising a ring emrjoumaiied 0n the bearing ring and having face teeth, and a plurality of nods each having a spur gcar at its inner end in mesh with the face teeth; means including an annular passage in the ncscpiece open to an outer face thereof for-supplying fuel to the pumps; and a sealing plate detavzhably secured to the nosepiece for closing the passage.

LLOYD E. JOHNSON.

CARL R. MAXWEIL. 

